Re: Is {{}} a valid construct?

> Your problem here is a result of your difficulty with the difference
> between {} and {{}}.
>
> I said "NOT {es}"
> You changed it to "NOT es"

Ok, lets have it your way:

U = {{}, apple, orange}
NOT {apple, orange} = {{}}
NOT {apple} => {{}, orange}
NOT {{}} => {apple, orange}
NOT {} => {{}, apple, orange}

In the last line, NOT {} produces a set that includes the thing being NOTed namely {}. This is illogical. Received on Tue Feb 06 2007 - 23:49:05 CET